JPS6235224B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tubular incandescent light bulb for copying machines, and more particularly to an elongated tubular incandescent light bulb containing a built-in filament having a non-light emitting portion for use in electronic copying machines.

A large amount of research and a large number of inventions have already been disclosed regarding elongated tubular incandescent light bulbs containing a filament having a non-light emitting part, which are used in electronic copying machines.

By the way, the recent trend in electronic copying machines, which are the applications for this type of light bulb, is towards faster copying speeds and lower power consumption, and for this reason strict conditions are also required for the tube-type incandescent light bulbs used in copying machines. It's starting to look like this.

In other words, in order to achieve high-speed copying, it is necessary to increase the scanning speed at which the tube-shaped incandescent lamp scans the document, so the filament of the tube-shaped incandescent lamp must have sufficient vibration resistance. be done.

On the other hand, when trying to achieve lower power consumption, as a result of the use of highly sensitive photosensitive materials as the power consumption of tube-type incandescent lamps decreases, light distribution and changes in light intensity of the tube-type incandescent lamps are reduced. As a result, higher accuracy of light distribution, narrower tolerances for changes in light amount, and other constraints are required.

In response to the above requirements, in tube-type incandescent light bulbs for copiers, the filament must not only have light-emitting and non-light-emitting parts arranged in succession, but also precisely determine the positions of the light-emitting and non-light-emitting parts. It is necessary that the shape of the filament be held securely in its intended position with great vibration resistance. In order to obtain excellent vibration resistance, the weight of the filament needs to be sufficiently reduced, and the filament needs to be held integrally with the light bulb with a large supporting force.

In general, tubular incandescent light bulbs for copying machines are broadly classified into the following types based on the structure of their filaments.

(a) Segment method A method using a filament formed by alternately connecting a plurality of light-emitting segment members and non-light-emitting segment members separate from the light-emitting segment members (for example, Japanese Patent Publication No. 10917/1983) (b) Short bar Method A method using a filament in which a shot bar is inserted into a predetermined part of a continuous long coil filament and the part is short-circuited (Utility Model Act 1973-
(359 Publication, Japanese Utility Model Application Publication No. 50-116979)) (c) Skip-winding method A coil portion of a continuous coil filament at a predetermined position is stretched, thereby forming a "skip-winding section" in which light emission is suppressed. Using a filament (US Pat. No. 3,295,007) However, all of these types of tube-type incandescent light bulbs have advantages and disadvantages.

For example, in the short bar type (b), the non-light-emitting part is formed by inserting the short bar into a long coil filament, so not only is the coil portion of the non-light-emitting part wasted, but also the short bar is inserted into a long coil filament. The weight of the non-light-emitting part becomes large, and since it is difficult to arrange the support, sufficient supporting force cannot be obtained, and overall there is a drawback that large vibration resistance cannot be obtained.

Basically, as a modified type belonging to this method, Publication of Utility Model Publication No. 52-7110, Publication of Utility Model Publication No. 52-7110,
The one described in Publication No. 7109 is known. In these filaments, a short-circuiting metal member is provided around the outer periphery of the portion of the long coil filament that should be the non-light-emitting part, and supports are provided at both ends of the short-circuiting metal member that extend outward and come into contact with the inner surface of the envelope. However, in these devices, the coil portion in the non-light emitting portion is wasted and the weight of the portion increases, and furthermore, a shorting metal member is attached to the outer periphery of the elastic coil filament. Therefore, it is difficult to sufficiently communicate between the two, and as a result, it is not possible to improve the positional accuracy of the light emitting part, and it is also impossible to obtain high vibration resistance.

In addition, in the case of the skip winding method (c), waste of the coil filament can be prevented, but the strength of the stretched single wire part (non-light emitting part) is low, and therefore the filament itself has low vibration resistance.
Disadvantages: It is necessary to support the entire filament by arranging many supports separate from the filament, and it is difficult to provide the supports, and it is also difficult to position the light emitting part, making it impossible to obtain an accurate light distribution. There is.

On the other hand, in the segment method (b),
Since the filament is constructed by connecting a plurality of light-emitting segment members alternately with separate non-light-emitting segment members, there is no waste in the entire filament, and therefore the weight of the filament can be sufficiently reduced. Basically, it is advantageous in that it is easy to obtain a large supporting force by forming the support portion on the non-light emitting segment member. However, since there are many connection points between the light-emitting segment members and the non-light-emitting segment members, there is a problem that the positional accuracy of the light-emitting segment members tends to be low and it is difficult to obtain a desired light distribution.

Specifically, in the tubular incandescent light bulb described in Utility Model Application Publication No. 50-93079, a ring-shaped support part is formed at both ends of a linear center part, and the ring-shaped support part of this ring-shaped support part is Using a non-luminous segment member formed of a single bar, the connecting leg extends linearly outward from the base, and the connecting leg is inserted into a coiled connecting portion formed at the end of the luminescent segment member. In this configuration, (i) straight connections at both ends of the non-light emitting segment members are provided within the coiled connections at the ends of each light emitting segment member; When the legs are inserted and connected, the light emitting segment members tend to slide against each other, causing misalignment of the light emitting segment members, making it difficult to accurately position them, and thus making it difficult to obtain accurate light distribution. Above, there is a high risk that the connection will come loose.

(ii) In non-light-emitting segment members, the elastic ring-shaped support part is located inside the connecting leg part, so the ring-shaped support part cannot have high shape accuracy. Since there is a large variation in distance and, ultimately, a large variation in the length of the non-light emitting segment members, it is difficult to obtain a desired light distribution.

(iii) In a non-light-emitting segment member, it is essential to position the connecting leg portions at both ends, and supporting portions cannot be located at both ends.
The spacing between the two ring-shaped support parts is small, so a large supporting force cannot be obtained, and the vibration resistance is poor.

There is a drawback.

In addition, the one described in Japanese Utility Model Application Publication No. 51-36276 is a short-circuiting core in which a coil-shaped connection part with a coarse pitch is formed at both ends of a light-emitting segment member, and a locking part is formed at the end of the coil-like connection part. A long filament is constructed by inserting a rod, and this filament is supported by separate supports at both ends of the core rod. In such a configuration, (i) the support Since the part and the core rod are not integrated and the light emitting segment member is not directly supported by the supporter, the filament cannot be supported sufficiently and the vibration resistance is low.

(ii) Since a separate supporter is used for the light-emitting segment member and the non-light-emitting segment member, the number of parts increases, and the number of connection points increases accordingly;
Also from this point of view, great vibration resistance cannot be obtained.

(iii) In the case of locking by the protrusions at both ends of the core rod, there is a high possibility that the lock will easily come off because the pitch interval of the coiled connecting portion is large and the coil has elasticity.

However, the vibration resistance is low, the light emitting part is easily misaligned, and the light distribution is likely to change.

In view of the above-mentioned circumstances, research is being carried out to improve each method in order to meet the current requirements. This is because each type of filament is constructed according to its own unique design concept, so it is virtually impossible to extract only the advantages of one type and apply them to another type of filament.

For example, the non-luminescent segment member shown in Japanese Utility Model Application Publication No. 50-93079 and the non-luminous segment member shown in Japanese Utility Model Application Publication No. 52-7109 and Japanese Utility Model Application Publication No. 52-7110 are each Although they are similar in terms of only the shape of the support portion, the functions required of the non-light-emitting segment members are completely different, and one cannot be used for the other. This is because the restrictions or requirements for connection or attachment to the light-emitting coil parts are completely different, making it actually impossible to connect, or even if not impossible, assembly becomes extremely complicated and impractical. .

Due to the above-mentioned circumstances, at present, a fully satisfactory tube-shaped incandescent light bulb for copying machines has not been provided, and active research and development is still being carried out in search of a more suitable one.

The object of the present invention is a tubular incandescent light bulb for copying machines having a segmented filament, and the object thereof is to provide a lightweight filament with high vibration resistance, and to achieve the desired light distribution. It is an object of the present invention to provide a tube-shaped incandescent light bulb for a copying machine, which can reliably obtain a uniform distribution of light and has little variation in light distribution or light intensity.

The present invention is characterized by an elongated tubular incandescent light bulb for copying machines incorporating a filament formed by alternately connecting a plurality of light-emitting segment members and non-light-emitting segment members separate from the light-emitting segment members. In the above, the non-light-emitting segment member is made of a single metal bar and is composed of a straight short part, a bent part provided at both ends of this short part, and a support part connected to the bent part, and the light-emitting segment member is made of a single metal bar. The member includes a light-emitting coil portion, and a coil-shaped connecting portion that is connected to an end of the light-emitting coil portion and has a pitch interval larger than the coil pitch interval of the light-emitting coil portion and the diameter line of the metal bar related to the non-light-emitting segment member. and the short portion and the coil-like connecting portion are welded and fixed in a state where the end portion of the short portion of the non-light-emitting segment member is inserted into the coil-like connecting portion of the light-emitting segment member.

FIG. 1a is an explanatory diagram of the main parts of the tubular incandescent light bulb for copying machines of the present invention, b is an explanatory diagram showing the light-emitting segment member alone, FIG. 1c is an explanatory diagram showing the non-light-emitting segment member alone, The figure is an explanatory diagram of a method of connecting a light-emitting segment member and a non-light-emitting segment member.

In the figure, 1 is a quartz bulb, and 2 is a light-emitting segment member. This light-emitting segment member 2 consists of a light-emitting coil portion 2a and a coil-shaped connecting portion 2b with a coarse pitch interval. Reference numeral 3 denotes a non-light-emitting segment member, which is composed of one metal bar, and includes a straight short part 3a and a straight short part 3a.
The bent portion 3b provided at both ends of the
It consists of a ring-shaped support part 3c continuous to b.
The pitch interval between the coiled connecting portions 2b in the light-emitting segment member 2 is larger than the pitch interval between the light-emitting coil portions 2a and larger than the wire diameter of the bar of the non-light-emitting segment member 3.

The light-emitting segment member 2 and the non-light-emitting segment member 3 are, as shown in FIG.
The light emitting segment member 2 is assembled by pushing it in the direction shown by the arrow 4 while rotating the light emitting segment member 2 so as to twist a right-hand screw beyond the bent portion 3b, and then weld and fix it at one predetermined location. In this way, the light-emitting segment members 2 and the non-light-emitting segment members 3 are alternately connected to form one filament,
Placed inside valve 1.

As described above, the pitch interval of the coiled connecting portion 2b of the light emitting segment member 2 is adjusted to
, and larger than the wire diameter of the bar of the non-light-emitting segment member 3. Therefore, even if a metal bar with a large wire diameter is used as the metal bar of the non-light-emitting segment member 3, the light-emitting segment member 2
can advance over the bent portion 3b of the non-light-emitting segment member 3 while being rotated, making assembly easy, and since unnecessary force is not applied to the light-emitting segment member during assembly, the shape is not disturbed. Does not occur. In addition, both the light-emitting segment member 2 and the non-light-emitting segment member 3 can be easily manufactured with accurate shapes, so manufacturing the filament is extremely easy, and the position of the light-emitting coil portion 2a can be set accurately. The light emitting segment member 2
The position of the light does not fluctuate, and changes in light distribution and light amount are prevented from occurring.

To explain in detail, the non-luminous segment member 3
is the coiled connecting portion 2b of the light emitting segment member 2.
Since the ring-shaped support portions 3c are integrally provided at both ends of the linear short portion 3a to which the
In the end, the ring-shaped support parts 3c are located at both ends of the non-light-emitting segment member 3, and at the same time, the ring-shaped supports 3c are located closer to the light-emitting coil part 2a, resulting in a very large supporting force. can be obtained. As described above, the metal bar forming the non-light-emitting segment member 3 may have a wire diameter sufficiently larger than the pitch interval of the light-emitting coil portion 2a. It is sufficient for the metal bar to have a wire diameter of about 0.2 to 0.6 mm.

Further, in this non-light-emitting segment 3, it is easy to strictly regulate the length of the straight short portion 3a, and moreover, the length of the light-emitting segment member 2
Since it is easy to adjust the length of the portion of the coiled connecting portion 2b that is wound around the end of the straight short portion 3a of the non-light emitting segment member 3, the light emitting coil portion 2a can be positioned accurately. and in a connected state,
A state is obtained in which the light emitting segment member 2 is locked with the bent portion 3b formed integrally with the linear short portion 3a, and therefore there is no possibility that the light emitting segment member 2 will be misaligned.

As described above, according to the present invention, the segment method allows the light emitting segment members to be arranged with high positional accuracy despite having an extremely simple configuration, and there is no waste in the filament, making it lightweight. In addition, since a large supporting force is obtained for the non-light-emitting segment members, the filament can be reliably supported and the light-emitting segment members are prevented from being misaligned. It is possible to provide an extremely excellent tubular incandescent light bulb for copying machines with little change in light distribution and light intensity.

[Brief explanation of the drawing]

FIG. 1a is an explanatory diagram of the main parts of the tubular incandescent light bulb for use in a copier according to the present invention, FIG. 1b is an explanatory diagram showing the light-emitting segment member alone, and FIG. The explanatory diagram shown in FIG. 2 is an explanatory diagram of a method of connecting a light-emitting segment member and a non-light-emitting segment member. DESCRIPTION OF SYMBOLS 1... Quartz bulb, 2... Light emitting segment member, 2a... Light emitting coil part, 2b... Coiled connecting part, 3... Non-light emitting segment member, 3a... Straight short part, 3b... Bent part , 3c...Ring-shaped support part.

Claims (1)

[Scope of Claims] 1. A long tube-shaped incandescent light bulb for copying machines that incorporates a filament formed by alternately connecting a plurality of light-emitting segment members and non-light-emitting segment members separate from the light-emitting segment members, The non-light-emitting segment member is made of a single metal bar, and is composed of a straight short part, a bent part provided at both ends of this short part, and a support part connected to the bent part, and the light-emitting segment member is , consisting of a light-emitting coil portion, and a coil-shaped connecting portion connected to an end of the light-emitting coil portion and having a pitch interval larger than the coil pitch interval of the light-emitting coil portion and the wire diameter of the metal bar related to the non-light-emitting segment member, A copying machine characterized in that the short portion and the coil-like connecting portion are welded and fixed with the end portion of the short portion of the non-light-emitting segment member being inserted into the coil-like connecting portion of the light-emitting segment member. Tube type incandescent light bulb.